1. Field of Invention
The present invention relates to an outdoor umbrella, and more particularly to an adjustable rotation base for an outdoor umbrella, wherein the adjustable rotation base comprises a transportation arrangement adapted to selectively and conveniently transport the outdoor umbrella for a predetermined distance.
2. Description of Related Arts
A conventional outdoor umbrella usually comprises a supporting base, a central stem upwardly extended from the supporting base, and an awning extended from a top portion of the central stem to provide shading for a predetermined shading area under an awning attached onto the awning frame. This kind of conventional outdoor umbrella has widely been utilized all around the nation for shading sunlight and providing a place where a wide variety of outdoor activities may take place. In order to enhance the performance and function of a typical outdoor umbrella, many inventions have been made to incorporate with a typical outdoor umbrella for achieving additional utility functions of that outdoor umbrella. For example, solar energy systems and illumination systems have been developed provide an environmentally-friendly energy source and illumination to outdoor umbrellas.
Despite these developments, there exists one deep-seated problem which has not been adequately resolved by one skilled in the art. The problem is that the outdoor umbrella is difficult or inconvenient to move while being used in outdoor environment. The most typical instance is that when a user wishes to move the outdoor umbrella from one place to another in a campsite, he or she has to lift up the entire outdoor umbrella and carry it to the intended destination. If that user is unable to move the outdoor umbrella due to its heavy weight, he or she has to ask for help from other people. This scenario presents undue inconvenience and sometimes embarrassment to that user because he or she may actually have to ask the guests to help him or her to move the outdoor umbrella. This scenario is worsened by the fact that in order to stabilize the outdoor umbrella as a whole when it is standing on a ground surface, the supporting base is often disposed with water or sand (i.e. objects of high density) for preventing accidental toppling of the outdoor umbrella. Thus, a typical outdoor umbrella is likely to be very heavy in weight.
In order to inject mobility to a typical outdoor umbrella, one may think that installing some sorts of wheels would be helpful. The problem, however, is that when the user wishes the outdoor umbrella to be stationary for prolonged used, the wheels may actually cause accidental yet undesirable movement of the outdoor umbrella. Therefore, there exist circumstances in which the user of outdoor umbrella may not wish it to be movable. Simply installing wheels to the outdoor umbrella does not resolve this extra problem.